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How to convert a data frame column to numeric type?
... and this is not the most confounding thing, but it can confuse you, especially if you read this before rolling into bed.
Here goes: first two columns are character. I've deliberately called 2nd one fake_char. Spot the similarity of this character variable with one that Dirk created in his reply. I...
Which is preferred: Nullable.HasValue or Nullable != null?
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The compiler replaces null comparisons with a call to HasValue, so there is no real difference. Just do whichever is more readable/makes more sense to you and your colleagues.
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Ember.js or Backbone.js for Restful backend [closed]
... approach' to Backbone.js. They're different kinds of tools that target totally different end products. Ember's sweet spot is applications where the user will keep the application open for long periods of time, perhaps all day, and interactions with the application's views or underlying data trigger...
Convert Unicode to ASCII without errors in Python
...2018, using compressions like gzip has become quite popular (around 73% of all websites use it, including large sites like Google, YouTube, Yahoo, Wikipedia, Reddit, Stack Overflow and Stack Exchange Network sites).
If you do a simple decode like in the original answer with a gzipped response, you'l...
Git: cannot checkout branch - error: pathspec '…' did not match any file(s) known to git
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Try git fetch so that your local repository gets all the new info from github. It just takes the information about new branches and no actual code. After that the git checkout should work fine.
shar...
Exception.Message vs Exception.ToString()
...ntaining the exception type, the message (from before), a stack trace, and all of these things again for nested/inner exceptions. More precisely, the method returns the following:
ToString returns a representation of the current exception that is intended to be understood by humans. Where the excep...
How and/or why is merging in Git better than in SVN?
...ne, is much better merging than in traditional tools like SVN.
Is this actually due to inherent differences in how the two systems work, or do specific DVCS implementations like Git/Mercurial just have cleverer merging algorithms than SVN?
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How to force an entire layout View refresh?
...Invalidate the whole view. If the view is visible, onDraw(Canvas) will be called at some point in the future. This must be called from a UI thread. To call from a non-UI thread, call postInvalidate().
ViewGroup vg = findViewById (R.id.mainLayout);
vg.invalidate();
Now, when the Activity resume...
Calling clojure from java
Most of the top google hits for "calling clojure from java" are outdated and recommend using clojure.lang.RT to compile the source code. Could you help with a clear explanation of how to call Clojure from Java assuming you have already built a jar from the Clojure project and included it in the cl...
Professional jQuery based Combobox control? [closed]
...ately, the best thing I have seen is the jquery.combobox, but it doesn't really look like something I'd really want to use in my web applications. I think there are some usability issues with this control, but as a user I don't think I'd know to start typing for the dropdownlist to turn into a textb...